Partial Oil Change - Any Remedy?

volvo
v70

#1

Recently purchased an '02 Volvo V70. Low miles. ( 53K ) All oil changes were with synthetics. Switched out the tires, had the transmission fluid changed, and ran two doses of Techron in it, two weeks apart, and now it’s ready for an oil change.



Unfortunately, this model has an oil-cooler that Does Not Drain when the rest of the oil is drained! So, about a quart of dirty oil stays in the engine, and gets recycled permanently. This can’t be good.



Would it be OK to try this “stunt” to clean out the engine? Go to the service station and drain and refill with the cheapest “blended” oil possible without changing the filter cartridge. Then, after driving for a couple hours, drain and refill with the good stuff ( Mobil-1 5W40 ) and a new filter cartridge. The idea would be to remove as much old crud as possible.



Would it be worth the added time & money? Or is the life-expectantcy of this high-compression, turbo, engine so low that it doesn’t really matter?



In that same regard, is the Mobil-1 filter insert ( $20! ) really worthwhile in this situation? Thanks for your opinion.


#2

The leftover oil is still viable oil on the day you change it, assuming you change your oil frequently enough. The leftover oil is not poison to your engine. It doesn’t get “recycled permanently”. It’s not pristine, but neither is the rest of your “new” oil after 1000 miles.

It’s nothing to worry over or do “stunts”.


#3

You’ll never get every drop of oil out of your car even without a oil cooler. I really don’t see it hurting much. If you’re concerned just change it more frequently.

As for the Mobil-1 filter…I don’t see the need. Many people here (including myself) have had vehicles pass the 300k mile mark on nothing but Fram $3.50 filter with no engine failures or problems.


#4

This is not worth the trouble. “Old” oil does not become dangerous to your engine, it’s just depleted in the additives that wear out, and a little dirty. The new oil replaces the additives. No problem at all having that oil left in your car as you change it, I’d be surprised if it was a quart.

ps-the “old” Mobil 1 may even be better than the “new” cheap oil, depending on how often you’re changing, so your stunt may make things (slightly) worse, not better!


#5

Exercise in futility.

Whatever you do for oil changes in method is going to do little to change what happened the first 7yrs/53k miles.

Use the appropriate oil & filter that meets Volvo spec and leaves a comfy feeling and change away.

My parents have over 300k on a Volvo turbo engine(early 90’s) that has used mechanic dino and supplied filter every 3-5k miles or 6 months. No internal work and original turbo.